Members of the CLAN project at AT&T Laboratories-Cambridge developed a high-performance user-level network that delivered Gbps bandwidth and very low overhead and latency. The network interface made use of a novel primitive for synchronisation -- the Tripwire. I looked at the software needed to bring the performance benefits of this technology to applications. This included the low-level system software, protocol design and middleware. I developed a software implementation of the Virtual Interface Architecture that ran over the CLAN network, and performed better than commercial hardware implementations. I also developed a CORBA ORB that achieved latency of just 8 microseconds and handled up to 145,000 requests per second.